What are the set measurements for standard moly piston rings?
Out of vizards book its
.014-.018 top compression ring(these are not exact but very close, this is what i remember as are the other ones)
.018-.025 on 2nd compression ring
and on Both oil rings its .025-.050.
Now those seem a bit iffy..What should they be or is this what i need/want them to be?

For hyperuetectics the gap is different. There is a formula you use to figure what you need. It all depends on what the piston manufacturer and the ring manufacturer specify. I would go with what the piston manufacturer says first, unless it is less gap than what the ring manufacturer says. Always err to the big side.

KB hypereutectics run the top ring higher, & as a result the gap needs to be bigger due to the greater heat causing more expansion of the steel. A Federal Mogul guy told me their hyper's use the " normal" ring gap. The "normal" rule of thumb is .004" per inch of cylinder bore for a normally-aspirated engine. Here's the chart for KB's:

Determining piston ring gap is a case by case basis. Will you be running nitrous? a blower? extreme RPM? piston type? marine? These types of uses need to be addressed before a ring gap should be determined.

Keep one thing in mind, when in doubt go wider. Too wide of a ring gap has shown very little affect in dyno tests. Too narrow a ring gap causes all kinds of problems and none of them are very good for the overall life of the engine.

The are federal-mogul-sealed power-speedpro 9.35:1 hypereutectics..They didn't come with a sheet that shows the gaps for some reason..I will be turning around 5500rpm's.So what your saying is that i can use KeithBlacks chart and use those gaps on my speedpro's

NO. Don't use KB info for SP pistons. The ring end gap will be too wide. SP Hypers use standard ring end gap factors. You may go a little more to be safe. Use the ring manufactures guide as a starting point.

you posted a very wide range .012-.025 that is broad. If you are running nitrous, forced induction, etc.. then go on the wider side.

If this is a mild build for a street car then you don't need as wide of a gap.

To answer your question yes that range looks fine. If your pistons came with rings, check the end gap and see where it sits out of the box. They may not even be file fit rings (sure all rings can be filed), I would guess they came "pre-gapped"

As machineman said it depends on the application and you set the gap accordingly. You just really don't want them to butt or you will break the piston/s.

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